Granted Patent
Utility
US 4,968,028 · App. 07/359,632
Vertical jump exercise apparatus
Inventor:
Michael A. Wehrell
Patented Case
View Patent ↗
Granted: Nov 6, 1990
Filed: May 31, 1989
Inventor
Michael A. Wehrell
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.